I don't mean to get off the topic of your social anxiety, but what you have described here is beyond general assholery. I'd suggest reporting this to HR--this is harassment on basis on disability. There are two facets here: not only is this harassment within the workplace, but also the fact that it is illegal to discriminate against someone on basis of disability, a category into which OCD and other anxiety disorders fall. If your company does not address his behavior, they themselves will be in violation of providing a workplace for individuals who fall into a protected category. You are legally entitled to reasonable accommodation of your OCD/anxiety in the workplace. All of this is working off of the assumption that you're in the US/Canada--both have similar laws/precedents that would protect you (source: I studied bioethics in Canada).

I realize that this goes a step beyond HR castigating someone for being rude to a coworker, but I'm saying all this because what he's doing goes beyond being a jerk. He's violating your civil rights and creating a hostile work environment. I recommend that you start documenting what he does and when he does it. You don't have to file with HR if you don't want to, but it's good to have it on hand in case this person escalates.